Pictured are sensory hair cells on the skin of zebrafish that are clustered in rosette structures called neuromasts (stained magenta). Used to detect water stimuli, the information is sent to the brain by nerves called afferent fibres (green) prompting the fish to take necessary action. These hair cells are similar to those we use to hear, and so zebrafish are very useful for studying why these cells are so good at what they do and how to prevent damage. Hair cells have unique structures called ribbons that allow more neurotransmitter – chemicals stored in vesicles that enable the transmission of signals across nerve junctions or synapses – to be organised near the synapse ready for release when a stimulus occurs. Research has now found that zebrafish with larger ribbons have lower activity in the afferent fibres that respond more slowly to stimuli, despite having more vesicles. Proving bigger isn’t always better.
Written by Katherine Hardy
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